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  • Substituição de sorbato de potássio por conservantes naturais em recheio de banana: avaliação da estabilidade durante o armazenamento
    Publication . Carvalho, Teresa Bento de; Silva, Beatriz Nunes; Silva, Beatriz; Oliveira, Isabel; Azevedo, Miguel; Tomé, Elisabetta; Teixeira, Paula
    Introdução :Os conservantes de síntese química, como o sorbato de potássio, têm sido utilizados pela indústria alimentar para prevenir a deterioração microbiana. Contudo, a crescente exigência dos consumidores por alimentos 'naturais' e 'sem químicos', bem como as preocupações ambientais, têm levado tanto os consumidores como a indústria a procurar conservantes naturais alternativos, denominados 'clean label', para substituir os aditivos químicos convencionais. Objectivos: O presente estudo teve como objetivo avaliar a estabilidade durante o armazenamento (22 ℃ e 62% de humidade relativa) de um recheio de banana produzido a nível industrial, comercializado para utilização em produtos de pastelaria e panificação. O sorbato de potássio comumente utilizado foi substituído por conservantes "clean label" existentes no mercado, à base de extratos vegetais.
    2024-11-27Documento de conferência Acesso aberto Ver mais
  • O impacto dos cuidados paliativos nas idas ao serviço de urgência : revisão sistemática da literatura
    Publication . Machado, Gabriela Jorge Fernandes; Capelas, Manuel Luís Vila
    Introdução: Os doentes com necessidades paliativas recorrem frequentemente ao Serviço de Urgência (SU), o que acarreta sofrimento para os próprios e seus cuidadores. Os Cuidados Paliativos (CP) têm sido associados, em alguns estudos, a uma menor utilização do SU por parte dos doentes terminais. Assim, foi realizada uma revisão sistemática da literatura, com o objetivo de determinar o impacto dos CP na utilização do SU. Metodologia: Foi feita uma pesquisa em seis bases de dados – PUBMED, CINAHL, SCOPUS, MedicLatina, Web of Science e PsyArticles. Foram pesquisados estudos sobre o impacto dos CP nas idas ao SU, em doentes com idade superior a 18 anos, que incluíssem patologia oncológica e/ou não oncológica e qualquer das tipologias de CP. Foram incluídos ensaios clínicos, estudos de coorte, estudos caso-controlo e estudos transversais. Um segundo revisor independente participou na seleção dos estudos. Após selecionados os artigos, foram extraídos os dados e os resultados apresentados como análise quantitativa e meta-análise. Resultados: Foram incluídos 67 artigos, sobre patologia oncológica e não oncológica e abrangendo as várias tipologias de CP – CP domiciliários, hospices, Unidades de Cuidados Paliativos (UCP) e consulta. A maioria dos estudos demonstrou um impacto positivo dos CP na utilização do SU. Através da meta-análise, obteve-se um odds ratio de 0,439, o que nos permite afirmar que os CP, de acordo com este estudo, permitem reduzir as idas ao SU em 2,3 vezes. Conclusões: A presente revisão sistemática da literatura demonstra evidência de que os CP estão associados a uma menor utilização do SU por parte dos doentes com necessidades paliativas.
    2024-11-27Dissertação de mestrado Acesso aberto Ver mais
  • Da teoria à prática : relatório de estágio na RSB - Comunicação na Imagem
    Publication . Silva, Jorge Duarte Andrade de Melo Ferreira da; Neves, Jaime Sérgio de Oliveira
    Este é o relatório das atividades e aprendizagens obtidas durante o estágio realizado na RSB - Comunicação na Imagem, que proporcionou ao autor uma experiência abrangente e multifacetada no campo do motion design, onde aplicou os seus conhecimentos académicos na criação de animações e motion graphics para diversos projetos, projetos estes onde desempenhou funções sobretudo na pós-produção de vídeo, design de stands para exposições e criação de animações 3D. Este estágio foi crucial para o desenvolvimento profissional, permitindo ao estudante adquirir e aperfeiçoar competências técnicas e criativas nas diversas áreas do design e multimédia, consolidando a formação e preparação para futuros desafios na área da comunicação visual.
    2024-11-27Dissertação de mestrado Acesso aberto Ver mais
  • Comparative analysis of fatty acid profiles in listeria monocytogenes isolates from food processing environments grown at 37 ºC and 10 ºC: exploring potential persistence markers
    Publication . Magalhães, Rui; Machado, Manuela; Teixeira, Paula
    Introduction: Listeria monocytogenes, the causative agent of listeriosis, is a major foodborne pathogen. It is a ubiquitous, facultative anaerobic, gram-positive bacterium. Listeriosis can be a severe illness particularly affecting vulnerable groups: the elderly, immunocompromised individuals, pregnant women and neonates. Listeria monocytogenes exhibits remarkable adaptability to diverse and challenging environments, demonstrating an exceptional capacity to thrive in conditions such as refrigeration temperatures or high salt concentrations or other factors found in food processing environments (FPE). This resilience is a key factor in its ability to persist within food processing facilities and proliferate in various food products. Only certain strains are routinely isolated from these FPEs (persistent strains) while others are isolated sporadically (non-persistent strains). Objectives: The aim of this study was to identify specific membrane fatty acids that could function as persistence markers within a collection of L. monocytogenes isolates from the GenoPhenoTraits4Persistence project culture collection. These markers may help distinguish between persistent (P) and non-persistent (NP) strains in the future. Conclusions: The results revealed the presence of key branched-chain fatty acids (iso-C15 and iso-C17), which are associated with the ability of L. monocytogenes to resist environmental stresses, particularly temperature fluctuations. Additionally, ΔC19 was detected in strains grown at low temperatures. This fatty acid is responsible for the adaption of membrane fluidity in response to environmental stress. These findings provide valuable insights into the lipid composition of L. monocytogenes and highlight potential markers of tolerance to adverse conditions (low temperature). These markers will be further investigated to understand whether they play a role in persistence, providing a deeper understanding of the mechanisms underlying the bacterium's ability to adapt and survive in food processing environments.
    2024-11-27Documento de conferência Acesso aberto Ver mais
  • The resilience of listeria monocytogenes to environmental stressors
    Publication . Gonçalves, Catarina; Ferreira, Vânia; Magalhães, Rui; Teixeira, Paula
    Introduction: listeria monocytogenes is a significant foodborne pathogen capable of causing severe listeriosis, particularly in vulnerable people [1]. To prevent its spread, effective disinfection strategies are essential. Quaternary ammonium compounds, like benzalkonium chloride, and peracetic acid are commonly used biocides in food processing environments. However, L. monocytogenes can exhibit remarkable resilience, particularly in high- salt conditions. This ability to survive in harsh environments, combined with its tolerance to certain disinfectants, is a persistent threat to food safety. Purpose: this study evaluated the impact of high salt concentrations and common disinfectants, benzalkonium chloride and peracetic acid, on the viability of various L. monocytogenes strains. The goal was to understand how environmental stressors affect the survival and persistence of this foodborne pathogen in food processing environments.
    2024-11-27Documento de conferência Acesso aberto Ver mais
  • Microbiological safety of urban farms in the Porto metropolitan area
    Publication . Rezende, Lourenço Pinto de; Barbosa, Joana Bastos; Teixeira, Paula
    Introduction: With new, more fast-paced lifestyles, the necessity for proximity to industrialized and highly populated cities has led to the migration of citizens from rural areas to urban centers in ever-growing numbers. These cities are, however, extremely dependent on external food resources. Urban food production has been encouraged to reduce this dependency on the rural agricultural output, with community, collective and private farms appearing throughout cities over the last few decades. Beyond enhancing food security, urban agriculture is recognized for promoting healthier lifestyles, fostering social interactions, and raising environmental awareness. Despite these advantages, the safety of consuming urban-grown produce remains a concern. Results: 10 out of 12 farms had lettuce samples exceeding acceptable TVC standards (6 log CFU/g). Six lettuce samples exceeded the limit of 4 log CFU/g for Enterobacteriaceae. Two lettuce samples exceeded the limit of 3 log CFU/g for E. coli. Bacillus cereus detected at high levels in soil, compost, and/or lettuce, often above satisfactory limits but below the estimated infectious dose of 5 log CFU/g. Contamination levels were significantly lower in the edible parts of wild cabbage compared to lettuce. Listeria monocytogenes was found in one lettuce and one cabbage sample. Salmonella spp. was detected in cabbage samples from one farm. Conclusions: These findings call attention to the public health risks associated with the current state of urban farming in Porto, particularly due to the presence in high levels of E. coli, B. cereus, and the contamination with L. monocytogenes, and Salmonella spp. Although these products require washing and, in some cases, cooking before consumption, these high bacterial counts underscore the need for stricter hygiene protocols and better food safety practices. Therefore, improving on-farm sanitation and guiding both farmers and consumers in learning how to handle these products correctly is essential to mitigate risks and ensure the long-term sustainability of urban agriculture. Addressing these concerns will be crucial to guarantee public health and the benefits of urban agriculture.
    2024-11-27Documento de conferência Acesso aberto Ver mais
  • Impacto dos programas de cuidados paliativos na comunidade nos resultados económicos : uma revisão scoping
    Publication . Lucas, Maria Isabel Bessa Cruz de Sá e; Capelas, Manuel Luís Vila
    Introdução: Instituições de saúde em todo o mundo têm implementado cada vez mais programas de Cuidados Paliativos (CP) na comunidade, seguindo as recomendações da Organização Mundial de Saúde, para garantir a sua acessibilidade e sustentabilidade. Estes programas têm demonstrado melhorar a qualidade de vida dos doentes e reduzir a sobrecarga dos cuidadores. No entanto, embora existam estudos que analisam a eficácia clínica dos CP na comunidade, poucos abordam o seu impacto económico. Metodologia: De acordo com as directrizes do Joanna Briggs Institute, a revisão scoping adotou uma estratégia de pesquisa em três fases, com o objetivo de mapear a literatura existente sobre o impacto dos programas de CP na comunidade nos resultados económicos. A pesquisa, realizada em 2024, abrangeu cinco bases de dados (PubMed, CINAHL, PsycArticles, Scopus e Web of Science) e incluiu estudos em português, inglês e espanhol. Todas as palavras-chave e termos de índice identificados foram incluídos (exemplo: Conceito – Cost*; Conceito - "Home Palliative Care"). Dois revisores independentes analisaram os resultados, com a intervenção de um terceiro em casos de dúvida. Resultados: Do total inicial de 2209 artigos, foram incluídos 25 artigos publicados entre 1992 e 2024. Os resultados sugerem que os programas de CP na comunidade reduzem os custos médios e globais bem como de serviços de saúde, ao mesmo tempo que apontam para o impacto positivo sobre a utilização de cuidados hospitalares, internamentos, idas aos serviços de urgência, controlo de sintomas e avaliação do desempenho dos doentes e local de morte. Conclusões: Os programas de CP na comunidade aparentam gerar benefícios económicos significativos. Contudo, existe uma grande diversidade nos métodos de avaliação económica presentes nos estudos, dificultando comparações. Torna-se necessária a padronização, a realização de estudos em países de rendimentos baixos e médios, e a avaliação do impacto económico a longo prazo destes programas.
    2024-11-27Dissertação de mestrado Acesso aberto Ver mais
  • A quantitative risk assessment model for Listeria monocytogenes in ready-to-eat smoked and gravad fish
    Publication . Gonzales-Barron, Ursula; Pouillot, Régis; Skjerdal, Taran; Carrasco, Elena; Teixeira, Paula; Stasiewicz, Matthew J.; Hasegawa, Akio; Mota, Juliana De Oliveira; Guillier, Laurent; Cadavez, Vasco; Sanaa, Moez
    This study introduces a quantitative risk assessment (QRA) model aimed at evaluating the risk of invasive listeriosis linked to the consumption of ready-to-eat (RTE) smoked and gravad fish. The QRA model, based on published data, simulates the production process from fish harvest through to consumer intake, specifically focusing on smoked brine-injected, smoked dry-salted, and gravad fish. In a reference scenario, model predictions reveal substantial probabilities of lot and pack contamination at the end of processing (38.7% and 8.14% for smoked brined fish, 34.4% and 6.49% for smoked dry-salted fish, and 52.2% and 11.1% for gravad fish), although the concentrations of L. monocytogenes are very low, with virtually no packs exceeding 10 CFU/g at the point of sale. The risk of listeriosis for an elderly consumer per serving is also quantified. The lot-level mean risk of listeriosis per serving in the elderly population was 9.751 × 10−8 for smoked brined fish, 9.634 × 10−8 for smoked dry-salted fish, and 2.086 × 10−7 for gravad fish. Risk reduction strategies were then analyzed, indicating that the application of protective cultures and maintaining lower cold storage temperatures significantly mitigate listeriosis risk compared to reducing incoming fish lot contamination. The model also addresses the effectiveness of control measures during processing, such as minimizing cross-contamination. The comprehensive QRA model has been made available as a fully documented qraLm R package. This facilitates its adaptation for risk assessment of other RTE seafood, making it a valuable tool for public health officials to evaluate and manage food safety risks more effectively.
    2024-11-27Artigo científico Acesso aberto Ver mais
  • High salinity and temperature contribute to Listeria monocytogenes persistence by inducing the VBNC state
    Publication . Azevedo, Mónica; Sousa, Mariana; Magalhães, Rui; Almeida, Gonçalo; Teixeira, Paula
    Introduction: Foodborne listeriosis has a low case rate but high mortality, posing a public health concern. Listeria monocytogenes can contaminate food-processing and storage environments, compromising the food supply chain. L. monocytogenes adapts to stresses like nutrient deprivation, extreme temperatures, and high salinity. Understanding its persistence mechanisms, including the ability to enter a viable but non-culturable (VBNC) state, is essential. Discussion: Microscopy using the BacLight assay showed significantly higher counts of viable cells compared to culturable cells detected using TSA and PALCAM, indicating the presence of VBNC cells. At 37 ºC, no colonies were observed with the plating method, yet viable cell counts remained high (BacLight assay). Similarly, at 8 ºC, viable cells outnumbered culturable bacteria. However, the low metabolic activity of L. monocytogenes at this temperature makes it less likely to enter the VBNC state. These results highlight the environmental conditions that promote the VBNC state in L. monocytogenes, offering insights for improving long-term storage, sterilization, and control measures in food products. Additionally, the findings emphasize the limitations of current culture-based methods in detecting VBNC bacteria, underscoring the need for more advanced detection techniques. Conclusion: Prolonged exposure to nutrient deficiencies, and high NaCl concentrations and temperature can induce the VBNC state of L. monocytogenes. VBNC cells evade detection by standard growth- based monitoring methods, thus improved detection methods, such as molecular screening techniques, are needed.
    2024-11-27Documento de conferência Acesso aberto Ver mais
  • Guinea-Bissau: avoiding the reputation of being a failed state
    Publication . Gonçalves, Paulo; Leandro, Francisco José
    This paper poses and answers the following research question: How may Guinea-Bissau overcome its permanent governance instability and avoid becoming a “failed state”? This question is particularly important, not only in the context of circumventing being exposed to the economic interests of external actors, but also, to understand the state domestic weaknesses. Guinea-Bissau is a partially archipelagic small state, with an interesting portfolio of natural resources, investment opportunities, and business prospects. The country has suffered decades of institutional instability and social fragility, resulting being rated as “failed-state”. Indeed, O’ Regan &Thompson (2013, p. 3) refer Guinea-Bissau as “(…) the first narco-state in Africa”. There are a number of perspectives to categorize a state as failed-state, but we are focused on the institutional approach and in a possible lack of state authority. As such, we assume that “states fail because they do not possess the political, economic and social capabilities to survive as states” (Hill, 2005; Gros, 1996, p. 456; Jackson, 2000, p. 296; Rotberg, 2004, p. 2; Zartman,1995, p. 5). Once the ideological cradle of colonial self-determination, Guinea-Bissau fought valiantly to gain independence (1963–1974), unilaterally proclaiming it on 24 September 1973 (Té, 2015, p. 30). Regrettably, after gaining recognition as a sovereign state, Guinea-Bissau has witnessed four effective coup d’états, 16 different attempts of coups d’état, one civil war, several parliamentary dissolutions, assassinations of politicians, interference of the militaries in executive functions and frequent change of political executives. Several reasons have contributed to this instability: (1) The interests of neighboring countries as well as an intense international influence; (2) The condition of being a post-colonial state, which is reflected in a number of factors such as poor literacy, health care and security (BTI, 2024); (3) The internal ethnic-religious clashes and the 1980 events, which lead qualified Cabo Verdean personnel to leave the country (Duarte Silva, 2006); (4) The meagre political control of the armed forces associated to a widespread corruption (BTI, 2024); (5) The short minded political culture within a semi-presidential system; (8) and the last but certainly not the least, the under-resourced and sloppy surveillance of borders (US Department of State, 2022, p. 5). All these factors jeopardized its economy, drained its resources, and exposed society to narco-trafficking. A struggle between the President Umaro Sissoco Embaló and the parliament regarding the amendment of the Constitution (among other issues), has further reignited political instability. Apart from the direct competition posed by Senegal, Guinea-Bissau has potential to become a reference economy in the region, and an entry door for the market of the Economic Community of West African States (ECOWAS) and the West African Monetary and Economic Union (WAEMU). However, hardly this will ever happen, without political stability and an urgent need of reform of the defense and security sectors. A transformation not only in its structures but, above all, in mentalities, based on the role of the military in a representative democracy-a semi-presidential political system. This research does not adopt any explicit theory (Creswell & Creswell, 2018, p. 64). Instead, it employs a descriptive-inductive qualitative methodology based on selected themes to evaluate how Guinea-Bissau can avoid becoming a failed state. The critical discussion of these themes, has been supplemented with interviews with Guinea-Bissau’s opinion leaders and representatives of its diaspora, as well as former Portuguese colonial agents. The authors wish to acknowledge that, to mitigate the insufficiency of official and academic qualitative data, we conducted a number of interviews and we used triangulated media sources. The relevant interview transcripts, were freely translated into English language. Finally, this research excludes the last two years (2022-2024) of current political leadership, under the President Embaló. During this period of time President Embaló dissolved the parliament twice, scheduled legislative elections for November 2024 and at the time we write, the presidential election has not been called yet. Therefore, the authors consider important the completion of this sequence of facts, to analyze his political action.
    2024-11-27Artigo de investigação Acesso aberto Ver mais